Feeding apparatus for pulverized material



8 7 E. H. HAMILTON ET AL FEEDING APPARATUS FOR PULVERIZED MATERIAL Filed Feb. 4. 1920 2 Sheets-Sham. 1

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E. H. HAMILTON TA! FEEDING APPARATUS FOR PULVERIZED MATERIAL Fina Eel). 1920 2 Sheets-Sheet 2 r- 7 {PK .7 I *1 Q 't: I .5

Patented Aug. 30, 1927.

UNITED STATES UNITED STATES BMELTING, REFINING & CHUSEI'I'S, A CORPORATION OF MAINE.

FEEDING APPARATUS FOR PULVEBIZED MATERIAL.

Application filed February 4, 1820. Serial 110. 358,388.

This invention relates to an apparatus for feeding pulverized coal and the like. The apparatus is particularly adapted for use in feeding pulverized coal 6 streams to a plurality of the blast furnace.

It has heretofore been proposed to supply fuel to a furnace by introducing pulverized coal into the furnace through the main 10 air blast of the tuyeres. Various forms of apparatus have been designed to perform the handling, distribution and introduction of the pulverized coal into the tuyeres of the furnace but a number of practical dilficulties have been encountered with all of the various forms of apparatus heretofore emloyed. These difficulties may, in eneral, e traced to the tendency of the pu verized coal to cake and to thereby choke the conduit pipes, conveyors, or other means which have been employed to feed the coal to the furnace.

The present invention contemplates a construction of feeding apparatus which when used for the purpose of introducing pulverized coal into a furnace through the tu ares, maintains the coal in a mobile, unca ed condition at all times so that it ma flow easily in a manner analagous to a fiui and accordingly, be conducted through conduits into the furnace in regulated streams.

e apparatus is simple, inexpensive in construction, the number of movable arts few, and in eneral, is particularly a apted for practica? use in connection with metallurgical furnaces.

To these ends the feeding apparatus comprises in general a distributor having provision for converting andmaintaining the 40 pulverized coal ina mobile and uncaked condition adapted to flow and be handled in a manner similar to a fluid, means for feedtuyeres of a mg the pulverized coal to the distributor and means for conductin the mobile and uncaked pulverized coal mm the distributor into a combustion chamber of a furnace.

When the apparatus is utilized in metallurgical furnace operation, provision is made for conducting the mobile and uncaked coal to a luralitzy of the tuyeres of the furnace, and or fee ing it into the main air blast Sight feeds are also proof the tuyeres.

the rate and continuity of vided whereby in separate flow of the pulverized coal may be readily observed.

The distributor is an important feature of the apparatus and comprises in its preferred form a c lindrical chamber, a rotatable disk arrange horizontally within the chamber, and u on which the pulverized coal falls as it is fied through the top of the chamber. The centrifugal force set up by the rotating disk, operates to dispe rse'the pulverized coal in light, thin and uniform layers outwardly in all directions from the edge of the disk, where it falls into an annular trough arranged about the periphery of the disk. A plurality of openings in the bottom of the annular trou h communicate with several conduits leading to the points of use such as the tuyres of a furnace. The particular and important functions of" the distributor are first to maintain the pulverized coal in a loose, flufl'y, and mobile condition, and second to distribute it uniformly to the mouths of the several conduits so that it may flow flheit'lethrough in a manner analagous to a These and other features of the invention will be pointed out in the specification and claims.

In the drawings illustrating the preferred embodiment of the invention Figs. 1' and 2 are diagrammatic layouts of the ap aratus in end and side elevation, respective y, Fig. 2 being partly in section; Fig. 3 shows the distributor in section; Fi 4 is a detail showing the construction 0 the. injector by which the pulverized coal is fed into the main air blast of the tuyeres; and Fi 5 is a detail in section of one of the regu ating valves.

Referrin to the drawi the blast furnace 1O ot usual construction is shown as supported on'I-beams 12. Low pressure air is conducted through the blast pipe 13 from a source of suppl not shown, into the tuyeres 14 located in the lower part of the furnace 10. The construction and mode of operation of the blast furnace and tuyeres is in general well known and neednot be further described.

The supply of pulverized coal is preferably stored in a in 20 sup orted in any desired manner and prefera ly upon the frame. work of the furnace at a considerable pulverized con nace through a elevation above the tuyeres 14 so that the force of gravit may be utilized to flow the down to the tuyeres. The lower portion of the bin 20 tapers and is provided with an outlet opening communicating with the inlet of a screw conveyor 21 of any usual or preferred construction and of suificient capacity to supply the requisite amount of fuel to the furnace. The screw conveyor 21 is mechanically driven by a pulley 22 from any convenient source of ower. The pulverized coal is discharged y the screw conveyor 21 into a cylindrical chamber 23 of a distributor 24 through an openin 25 in the top thereof. The bottom wall 0 the distributor chamber 23 is provided with a raised central portion 26 and with a tapered side portion 27 forming an annular trou ll 28 around the periphery of the bottom 0 the chamber.

Provision is made for distributing the puiverized coal as it is fed in through the opening 25 of the chamber into and around the annular trough 28 and to this end a horizontal disk 30 is mounted on'the app)? end of a vertical shaft 32 journaled in a aring 33 at the center of the raisedportion 26 of the bottom of the chamber 23. A grease cup 36 p rmits lubrication of the bearing 33 and in order to permit access to the grease cup, the bottom wall of the chamber 23 is preferably of spider shape so that an operator may insert his hand through an opening and turn up the grease cup. A conical 'cap 37 is screwed on to the upper end of the vertical shaft 32 and serves as a baflie for deflecting the pulverized coal as it falls from the screw conveyor 21, on to different ortions of the surface of the horizontal dis 30. The vertical shaft 32 and horizontal disk 30 are rotated at considerable speed, bein driven from any convenient source 0 power through a sprocket 40, shaft 42 and bevel gears 43, 44.

The centrifugal force generated by the rotating horizontal disk 30 acts upon the pulverized coal as it falls through the opening 25 and operates to throw the coal outwardly beyond the edge of the disk in uniform layers and into the annular trough 28. The action of the horizontaldisk upon the pulverized coal also operates to convert it into a loose, flufl order to assist in maintainin the coal in the trough 28 in this desirable oose and uncaked condition, a plurality of paddles or stirring devices 40 are secured to the periphery of the disk and o crate, as the disk is rotated, to stir the pa verized'coal around the trough 28 and to maintain it at a uniformlevel therein. a

The pulverized coal is conducted from the annular trough .28 to the tuyeres of the furplurality of conduits 45, the

upper ends of w ich cooperate with tapered and mobile condition and in holes 46, located at spaced intervals around the bottom of the annular trough 28. A regulating valve 47 is interposed between the upper end of each conduit 45 and the tapered hole 46 and operates to control the rate of flow of the pulverized coal through each conduit. The construction of the regulatin valve 47 is shown in detaii in Fig. 5 and comprises a valve of well known construc tion having openings 48, 49 and 50 of difi'erent sizes. It is to be observed that the taper of the holes 46 and 48, 49 and 50 is in the opposite direction to the flow of the pulverized coal from the annular trough 28 through the conduits. By arrangin the taper of these holes as shown, the ten enc of the holes to choke is diminished to a minimum. It will he observed that the flow of pulverized coal through each conduit 45 may e convenientl regu ated and therefore the supply of fue to any particular-tuyere of the furnace may be re ulated independently of the supply to any 0518!, so that variations in combustion in diflerent portions of the furnace may be com nsated for.

All of the conduits 45 lead downwardl to within a short distance of the several tuyeres and the ends thereof terminate above hoppers 55 connected to openin in the suction chambers of a plurality of igh pressure pneumatic injectors 56. igh pressure air is introduced into each injector through a nozzle 58, and the aspirating effect of the air operates to draw the pulverized coal from the hopper 55 into the main air blast of the tuyere with which it is carried into the furnace and burned. As the pulverized coal drops from the ends of the conduits into the hoppers 55 a ap sight feed is formed thereby enablin t e rate andcontinuity of the flow in eac conduit to be readily observed by an operator. This feature is of considera le practical importance and facilitates the control and operation of the furnace. Furthermore the sight feed enables the hi h pressure air of the pneumatic injectors to be regulated with nicety so as to give suilicient suction to draw the pulverized coal into the air blasts of the tuyeres and at the same time to utilize a minimum amount thereof. In this manner economy in the production of hi h pressure air is efiected.

t will be observed that the invention in its preferred embodiment is particularl adapted for metallurgical furnace wor where it is desirable to feed the pulverized coal in equal or regulated amounts and rates to a plurality of ints, preferably to a In.- rality of the tuy res of the furnacm. he distributor produces a constant level or head of pulverized coal above the mouth of each conduit so that the flow of pulverized coal down through each of the conduits is maintained uniform. The stirring devices serve coal at a constant level, to keep the mouths of the conduits free and to thereby prevent clogging and choking of both the conduits the regulating valves.

It will also be observed that extreme flexibility of operation is obtained by the use of the resent feeding apparatus in that it is POSSlblB to close the regulating valves of any number of the conduits and still maintain by manipulation of the valves in the remaining conduits, a uniform rate of fuel feed through the remaining conduits. In this manner difficulties with the individual tuyeres of the furnace are prevented from disabling the entire feed apparatus so that under practically all operating conditions a uniform and normal rate of fuel feed to the furnace is obtained.

While the invention has been illustrated and described as embodied in an apparatus adapted to feed pulverized coal to a metallurgica] furnace, certain features of the invention are capable of being employed for other purposes in oder to distribute pulverized material to a plurality of points of use.

Having thus described the invention what is claimed is:

V. 1. The combination with a blast furnace having a lurality of tuyeres through which pulverize fuel is delivered to the furnace, of means for deliverin pulverized fuel to each tuyere, a conduit or each delivery means through which the fuel flows, a trough from the bottom of which the conduits lead, and means for delivering pulverized fuel into the trough in an uncaked mobile condition and for maintaining it at a uniform depth above the mouths of the conduits.

2. The combination with a blast furnace having a plurality of tuyeres, of a distributor comprising a chamber, a rotatable disk horizontally mounted in said chamber, an annular trough located in the bottom of the chamber about the periphery of said disk, a plurality of openings in the bottom of said annular trough, means for supplyin the ulverized material to the upper end 0 said istributor, a plurality of conduits cooperating with the openings in the bottom of the annular trough of the distributor and leading downwardly to within a short distance of the t-uyeres, a plurality of valves adapted to control the flow of the pulverized material through the said conduits, a plurality of pneumatic injectors cooperating with the ends of said conduits and with the tuyeres for feeding the pulverized material into the furnace.

3. The combination with a blast furnace having a plurality of tuyeres, of a distributor comprising a chamber, a rotatable disk horizontally mounted in said chamber, an annular trough located in the bottom of the chamber about the periphery of said disk a stirring device secured to the disk and adapted to traverse around in said annular trough, a lurality of openings in the bottom of said annular trough, means for supplying the pulverized material to the upper end of said distributor, a plurality of conduits cooperating with the openings in the bottom of the annular trough 'of the distributor and leading downwardly to within a short distance of the tuyeres, a plurality of valves adapted to control the flow of the pulverized material through the said conduits. a plurality of pneumatic injectors cooperating with the ends of said conduits and with the tuyeres for feeding the pulverized material into the furnace.

EDWARD H. HAMILTON. LEOTIS KIRK.

coal at. a constant level, to keep the mouths of the conduits free and to thereby prevent clogging and choking of both the conduits ized material the regulatin valves.

It will also be observed that extreme flexibility of operation is obtained by the use of the present feeding apparatus in that it is possible to close the regulating valves of any number of the conduits and still maintain by manipulation of the valves in the remaining conduits, a uniform rate of fuel feed through the remaining conduits. In this manner difficulties with the individual tuyeres of the furnace are prevented from disabling the entire feed apparatus so that under practically all operating conditions a uniform and normal rate of fuel feed to the furnace is obtained.

While the invention has been illustrated and described as embodied in an apparatus adapted to feed pulverized coal to a metallurgical furnace, certain features of the invention are capable of being employed for other purposes in oder to distribute pulverto a plurality of points of use.

Having thus described the invention what is claimed is:

1. The combination with a blast furnace having a lurality of tuyeres through which pulverized fuel is delivered to the furnace, of means for delivering pulverized fuel to each tuyere. a conduit for each delivery means through which the fuel flows, a trough from the bottom of which the conduits lead, and means for delivering pulverized fuel into the trough in an uncaked mobile condition and for maintaining it at a uniform depth above the mouths of the conduits.

2. The combination with a blast furnace having a plurality of tuyeres, of a distributor comprising a chamber, a rotatable disk horizontally mounted in said chamber, an annular trough located in the bottom of the chamber about the periphery of said disk, a plurality of openings in the bottom of said annular trough, means for supplyin the pulverized material to the upper end 0 said istributor, a plurality of conduits cooperating with the openings in the bottom of the annular trough of the distributor and leading downwardly to within a short distance of the t-uyeres, a plurality of valves adapted to control the flow of the pulverized material through the said conduits, a plurality of pneumatic injectors cooperating with the ends of said conduits and with the tuyeres for feeding the pulverized material into the furnace.

3. The combination with a blast furnace having a plurality of tuyeres, of a distributor comprising a chamber, a rotatable disk horizontally mounted in said chamber, an annular trough located in the bottom of the chamber about the periphery of said disk a stirring device secured to the disk and adapted to traverse around in said annular trough, a lurality of openings in the bottom of sai annular trough, means for supplying the pulverized material to the upper end of said distributor, a plurality of conduits cooperating with the openings in the bottom of the annular trough 'of the distributor and leading downwardly to within a short distance of the tuyeres, a plurality of valves adapted to control the flow of the pulverized material through the said conduits. a plurality of pneumatic injectors cooperating with the ends of said conduits and with the tuyeres for feeding the pulverized material into the furnace.

EDWARD HQHAMILTON. LEOTIS KIRK.

CERTIFICATE. OF CORRECTION.

Patent No. 1,640,110.

Granted August 30, 1 927, to

EDWARD H. HAMILTON ET AL.

It is hereby certified that error appears in the printed specification of the above numbered patent requiring correction as follows: Page 1, line 86, for the numeral "2" read "1";

Signed and sec ed page 3, line 24, "order"; and that the aid Letters Patent therein that the same may conform to the thin 11th day of Octohenh. D. 1927.

for the misspelled word "oder" read should be read with these corrections record of the M. 1. Moore, Acting Commiuioner of Patentc.

cue in the Patent Office.

CERT l? l GATE 0F CORRECTION.

Patent No. L640, 770. Granted August 30, 1927, to

EDWARD H. HAMILTON ET AL.

It is hereby certified that error appears in the printed specification of the above numbered patent requiring correction as follows: Page 1; line 86, for the numeral "2" read "1"; page 3, line 24, for the misspelled -word "oder" read "order"; and that the aid Lettera Patent ahould be read with these corrections therein that the same may conform to the record of the caae in the Patent Office.

Signed and sea ed the 11th day of October, A. D. 1927.

M. J. Moore,

Seal. Acting Commiaaioner of Patenta. 

